1. Technical Field
The present disclosure relates to a computer vision and in particular to a trajectory analyzing apparatus and method that analyze a result obtained by tracking a moving object over pictures.
2. Description of the Related Art
A process of tracking the movement of a moving object over pictures by extracting the moving object from time-series frames forming the pictures (hereafter referred to as the “moving-object tracking process”) have been utilized in various fields in recent years.
In the moving-object tracking process, typically, the image features and position of a moving object extracted from the preceding and earlier frames are used to search for the moving object in the subsequent frame. Such a moving-object tracking process allows for tracking of the moving object with high accuracy; however, this process causes accumulation of errors and tends to reduce the tracking accuracy as the moving object moves away from the start point of the trajectory thereof.
In view of the foregoing, there have been developed technologies of improving the tracking accuracy by tracking a moving object from the first picture along the forward direction of the time axis and tracking a moving object from the last picture along the backward direction of the time axis. One example of such technologies is Japanese Unexamined Patent Application Publication No. 2008-243187.
A technology disclosed in Japanese Unexamined Patent Application Publication No. 2008-243187 (hereafter referred to as the “related art”) selects one of multiple moving-object tracking algorithms and tracks a moving object along both the forward and backward directions of the time axis. If there is a large difference between the obtained forward and backward trajectories, the related art changes the moving-object tracking algorithm to another to perform a moving-object tracking process again.
This related art is less likely to accumulate errors of the tracking accuracy, that is, allows for use of a moving-object tracking algorithm which is more suitable for the moving object to be tracked (hereafter referred to as the “target moving object”) and thus allows for improvements in tracking accuracy.